From the BBC: http://www.bbc.co.uk/news/world-eur
Russian author Boris Akunin reveals female pseudonym
A digitally altered photo of Akunin was used for "Anna Borisova"
Boris Akunin, the Russian author of the Erast Fandorin detective series, has revealed he wrote several books under the female pseudonym Anna Borisova....
Noting that all of his Borisova novels put together had sold about 200,000 copies - a fraction of what one Fandorin book might sell - Akunin said of his alter ego: "She was a great lady but everything comes to an end and the time has come to part company."
Great test case here.